Secrecy Analysis and Error Probability of LIS-Aided Communication Systems under Nakagami-m Fading

Abstract

Large intelligent surfaces (LIS) are a new trend to achieve higher spectral efficiency and signal-to-noise ratio in mobile communications. For this reason, this paper proposes metrics to analyze the performance of systems with multiple antennas aided by LIS and derive the spectral efficiency, secrecy outage probability, and bit error probability in an environment with Nakagami-m distributed fading. In addition to an eavesdropper, there is a single-antenna user, an array of antennas at the transmitter side and the possibility of a direct link between transmitter and receiver. This study assumes that the LIS performs non-ideal phase cancellation leading to a residual phase error that follows a Von Mises distribution, and shows that the resulting channel can be accurately approximated by a Gamma distributed SNR whose parameters are analytically derived. From these formulas, it is possible to evaluate the effect of the strength of the line-of-sight link by varying the Nakagami parameter, m.

Aerial intelligent reflecting surface for improving the secrecy performance of wireless systems with hardware impairments

“…Consequently, this assumption is considered reasonable and has been widely utilized in previous works. 4,15 where h SD is the channel from S to D; h l and k l are, respectively, the channels from S to the l th RE and from the l th RE to D; φ l is the phase of the l th RE of AIRS; x S is the transmitted message of S with  x S j j 2 È É ¼ P S , where P S denotes the average transmit power of S; η D is the added distortion noise induced by HIs at receiver D; z D $ CN 0, σ 2 D À Á is the Gaussian noise at D.…”

“…Besides simulating the SOP of the considered AIRS-HI systems (denoted by "AIRS-HI"), the SOPs of the AIRS-ID systems (denoted by "AIRS-ID"), HI systems without AIRS (denoted by "No-AIRS-HI"), and ID systems without AIRS (denoted by "No-AIRS-ID") are also provided to clarify the benefits of AIRS as well as the effects of HIs. Unless otherwise stated, the parameter settings are: (17)); N F ¼ 10 dBm; σ 2 0 ¼ À174 dBm/Hz; G rx ¼ G tx ¼ 5 dB (refers to (15) and ( 16)); m jh SD j ¼ m jh SE j ¼ m jh l j ¼ m jk l j ¼ m. Moreover, to compute the receiver-transmitter distances, the 3D coordinates are utilized to express the positions of S, AIRS, D, and E. Specifically, the positions of S, D, and E are fixed, that is,…”

Secrecy Analysis of a Mu-MIMO LIS-Aided Communication Systems under Nakagami-m Fading Channels

“…where γ E is the SINR of the channel between the source and the eavesdropper and γ D is the SINR of the channel between the source and the correct destination (the user). Ferreira et al [15] derived the exact formula of the SOP for a Nakagami-m distributed eavesdropper channel as (34).…”

“…In addition, it is prudent to consider a possible direct channel between the user and the transmitter and channels between the transmitter and an eavesdropper; without losing the generality, we can consider all these channels as Nakagami-m. However, each one has its parameter m ; for users close to the base station, the parameter m in the Nakagami distribution for the direct channel will be large between the user and the transmitter and may not even need the LIS, whereas a user outside the LoS may have and fall into the Rayleigh fading scenario (without LoS), where the LIS will create a channel resulting from the composition of all the links that result in a channel with LoS and a lower bit error rate [ 15 ].…”

“…The composite channel is the product of two channels with a Nakagami- m [ 14 ] distribution with different coefficients, modeling what goes to the LIS and what goes to the user, and a complex phase error modeled as a Von Mises distribution. Ferreira et al [ 15 ] obtained the distribution of the resulting channel considering only one antenna in the receiver; in this work, we approach a more complex and more comprehensive system model, which includes all the analyses made by the authors, for a special case in which the number of antennas of the user is unitary.…”